This module maintains a per-user, persistent table of key-value pairs.

INTERFACE UserState;

PROCEDURE Get (key: TEXT): TEXT;

Returns the value, if any, associated with key. Otherwise, it returns NIL.

PROCEDURE Put (key, value: TEXT);

Associates the pair (key, value) and updates the persistent storage.

PROCEDURE Init (dir: TEXT);

Initialize the persistent table from the contents of dir.

END UserState.